1

Source apportionment of PM in the PCM model

John Stedman

23 April 2010

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Presentation Structure

• Pollution Climate Mapping (PCM)– Overview of the project– Overview of the model

• PM10 and PM2.5 models for 2008– Introduction– Maps of some of the components– Verification plots– Source apportionment at monitoring sites– Source apportionment for population-weighted means

Pollution Climate Mapping (PCM)

• Policy Advice to Defra and the DAs – Brings together information from ambient measurements, emission inventories

and models

• Models– GIS-based PCM models

• Ambient air quality directive reporting, Policy support, AQS reporting, AQS review, AQEG

– Mapping current concentrations– Baseline & scenario based projections– Health impact assessment for scenarios

• SO2, NOx, NO2, PM10, PM2.5 ,Pb, CO, benzene, ozone, BaP, As, Cd, Ni, (Hg)

Project Manager: John Stedman

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PCM GIS-based models

• Maps built up from many layers

1. Regional (interpolated from rural measurements)2. Point sources modelled using dispersion model3. Area sources modelled using a dispersion kernel approach4. Other pollutant specific layers5. Roadside increment model

• Calibrated using automatic monitoring data from the AURN• 1 km grid resolutions + urban major road links

• Many similarities between ‘gaseous’ and ‘particle’ models, and some differences

• Particle model (PM10, PM2.5, As, Cd, Ni, Pb) components such as re-suspension consistent with each other and other components are consistent with the gaseous models

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PCM GIS-based models: inputs (1)

• Measurements– Rural measurements to define regional concentrations

− SIA, Cl– National network measurements to calibrate models

− AURN (FDMS)– Other measurements to verify models

− AURN TEOM VCM, partisol− AEA Calibration Club− ERG

• Emission inventories– 1 km x 1 km emission maps– Road link emissions– Emission projections

− NAEI year to base year and NAEI year to projection year (e.g. 2015)

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PCM GIS-based models: inputs (2)

• Met data– Area dispersion kernels– Point sources

• Model results– HARM/ELMO for SOA– EMEP for SIA emission sensitivity coefficients for projection

– VCM for PM10

– TRACK for regional primary PM

• Land cover map– For re-suspension modelling

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PCM GIS-based models: outputs

• GIS maps• Base year and projections

– Background 1 km x 1 km– Roadside ~ 9000 urban road links

• Background and roadside exceedance statistics– By zone

• Population-weighted mean background concentration– For health impact assessment, CBA

• Source apportionment– Policy development (MACC)– TEN – LAQM/DMRB

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PM10 and PM2.5 annual mean models for 2008• Pragmatic approach including many different layers

– Process based models as far as possible– Loosely based on ‘Pragmatic mass closure model’

• PM2.5 and PM2.5-10 for each component – Consistent models for PM10 and PM2.5

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PM10 and PM2.5 annual mean models for 2008• Secondary inorganic aerosol

– Interpolated from SO4, NO3 and NH4 measurements– Scaled for counter-ions and bound water, size fractions

• Secondary organic aerosol– HARM/ELMO model results

• Large point sources of primary particles– Explicitly modelled using ADMS

• Small point sources of primary particles– Small points model using a dispersion kernels derived using ADMS

• Regional primary particles– TRACK model using EMEP and NAEI emissions

• Area sources of primary particles– Dispersion kernels derived using ADMS– Calibrated using AURN measurements

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PM10 and PM2.5 annual mean models for 2008• Rural calcium rich dusts from soil resuspension

– Resuspension model – Emission depends on land cover and hour-by-hour met

• Urban calcium rich dusts– Surrogate spatial distribution based on population

• Regional iron rich dusts– Assumed constant 1 µg m-3 PM10

• Iron rich dusts from vehicle related resuspension– Resuspension model – Emission depends on HGV flow on major roads and hour-by-hour met

• Sea salt– Interpolated from Cl measurements– Scaled for– counter-ions

• Residual– Assumed constant 1 µg m-3 PM10

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Maps of some of the components

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Maps of some of the components

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a) Contribution to PM10 from rural Ca rich dusts associated with re-suspension from soils (g m-3)

b) Contribution to PM10 from urban Ca rich dusts associated with urban activities (g m-3)

c) Contribution to PM10 from regional Fe rich dusts (g m-3)

d) Contribution to PM10 from Fe rich dusts associated with vehicle movements (g m-3)

PM10 and PM2.5 in 2008 (g m-3)

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Verification plots

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Verification of background annual mean PM10 (gravimetric) model 2008

Verification of roadside annual mean PM10 (gravimetric) model 20079

0

5

10

15

20

25

30

35

0 5 10 15 20 25 30 35

Measured PM10 (µg m-3, gravimetric)

Mo

del

led

PM

10 (

µg

m-3

, g

ravi

met

ric)

National network FDMS(Calibration)Verification nationalnetwork gravimetricVerification sites VCM

Verification nationalnetwork TEOMVerification sites TEOM

Verification sites FDMS

Verification sitesgravimetricy = x

y = x + 50%

y = x - 50%

0

10

20

30

40

50

0 10 20 30 40 50

Measured PM10 (µg m-3, gravimetric)

Mo

del

led

PM

10 (

µg

m-3

, g

ravi

met

ric)

Calibration FDMS

Verification national network gravimetric

Verification sites VCM

Verification national network TEOM

Verification sites TEOM

Verification sites gravimetric

y = x

y = x + 50%

y = x - 50%

Source apportionment at FDMS monitoring sites 2008

15

0

5

10

15

20

25

30

Po

rt T

albo

t Mar

gam

(8)

Bir

min

gham

Cen

tre

(4)

Man

ches

ter P

icca

dilly

(4)

Sh

effie

ld C

entr

e (4

)

New

cast

le C

entre

(4)

Co

ven

try M

emor

ial P

ark

(5)

Live

rpoo

l Sp

eke

(5)

Wir

ral T

ranm

ere

(5)

Leic

este

r Cen

tre (6

)

So

uth

amp

ton

Cen

tre

(6)

Car

diff

Cen

tre (6

)

No

ttin

gham

Cen

tre

(6)

Hul

l Fre

eto

wn

(6)

Bri

sto

l St P

auls

(6)

Ply

mo

uth

Cen

tre

(6)

Ed

inbu

rgh

St L

eona

rds

(6)

Bla

ckp

ool M

arto

n (6

)

New

po

rt (7

)

So

uth

end-

on-S

ea (7

)

Pre

sto

n (7

)

Auc

hen

cort

h M

oss

(10)

PM

10 c

on

cen

trat

ion

(µ

g m

-3)

Site name (DfT area type)

Local sources

Traffic (brake and tyre wear)

Traffic (exhaust emissions)

Urban background sources

Other

Shipping

Aircraft

Off road mobile machinery

Domestic

Commercial

Industry

Traffic (brake and tyre wear)

Traffic (exhaust emissions)

Urban dusts

Regional background

Rural dusts

Secondary aerosol

Long range transport primary

Residual

Sea salt

Measured

Industrial Urban centre/ urban background/ suburban sites Rural

Source apportionment at FDMS monitoring sites 2008

16

0

5

10

15

20

25

30

35

40

To

wer

Ham

lets

4 -

Bla

ckw

all (

2)

Gre

enw

ich

9 -W

esth

orne

A

ve (3

)

Eal

ing

2 (F

DM

S) -

Act

on

To

wn

Hal

l (3)

Bex

ley

7 (F

DM

S) -

Th

ames

R

d N

ort

h (3

)

Gre

enw

ich

13 -

Plu

mst

ead

H

igh

Str

eet (

3)

Sw

anse

a R

oad

side

(7)

Ch

iche

ster

Ro

adsi

de

(FD

MS

) (10

)

PM

10

co

nc

en

tra

tio

n (

µg

m-3

)

Site name (DfT area type)

Roadside sites Local sources

Traffic (brake and tyre wear)

Traffic (exhaust emissions)

Urban background sources

Other

Shipping

Aircraft

Off road mobile machinery

Domestic

Commercial

Industry

Traffic (brake and tyre wear)

Traffic (exhaust emissions)

Urban dusts

Regional background

Rural dusts

Secondary aerosol

Long range transport primary

Residual

Sea salt

Measured

Source apportionment at TEOM VCM and Partisol monitoring sites 2008

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0

5

10

15

20

25

30

Lon

don

Har

lingt

on (3

)

Gra

ng

emou

th (8

)

Scu

nth

orpe

Tow

n (8

)

Lon

don

Blo

omsb

ury

(1)

Lon

don

Wes

tmin

ster

(1)

Lon

don

N. K

ensi

ngto

n (2

)

Lon

don

N. K

ensi

ngto

n P

AR

TIS

OL

(2)

Lon

don

Bex

ley

(3)

Gla

sgow

Cen

tre

(4)

Leed

s C

entr

e (4

)

Bo

urn

emou

th (6

)

Po

rtsm

out

h (6

)

No

rwic

h C

entr

e (7

)

Leam

ing

ton

Sp

a (8

)

Th

urro

ck (8

)

Auc

hen

cort

h M

oss

(10)

Har

wel

l (10

)

Har

wel

l PA

RT

ISO

L (1

0)

Ro

ches

ter S

toke

(10)

PM

10 c

on

cen

trat

ion

(µ

g m

-3)

Site name (DfT area type)

VCM and Partisol sites

Local sources

Traffic (brake and tyre wear)

Traffic (exhaust emissions)

Urban background sources

Other

Shipping

Aircraft

Off road mobile machinery

Domestic

Commercial

Industry

Traffic (brake and tyre wear)

Traffic (exhaust emissions)

Urban dusts

Regional background

Rural dusts

Secondary aerosol

Long range transport primary

Residual

Sea salt

Measured

Source apportionment for population-weighted means

180

2

4

6

8

10

12

14

16

Scotland Wales Northern Ireland Inner London Outer London Rest of England UK

µg m

-3

PM2.5 source apportionment 2008

Local traffic

Local non-traffic

Regional primary

Secondary PM

Other anthropogenicNon-Anthropogenic